public function filter_woocommerce_product_file_download_path($file_path, $product, $download_id) {

        // This block of code should run in a separate filter that's run before e2pdf's is run so we don't hack e2pdf.
        if ( isset( $_GET['recipient'] ) ) {
            $recipient = base64_decode( urldecode( $_GET['recipient'] ) );
            $file_path = str_replace( ']', ' extra="' . $recipient . '"]', $file_path ); // I'm 100% sure "extra=[string]" is not the way to modify the shortcode to receive our value, but... what is? HELP!
        }
        
        $file_path = $this->filter_content($file_path, $product->get_id(), true);
        return $file_path;
    }

/**
 * Append a meta from an order's line-items to download URLs for later retrieval
 */
function pbi_downloads( $downloads, $order_object ) {
	
	$order_items = $order_object->get_items();
	$downloadable_items = [];

	foreach( $order_items as $index => $item ) {
		if ( ! is_object( $item ) || ! $item->is_type( 'line_item' ) ) {
			continue;
		}
		if ( $item->get_product() && $item->get_item_downloads() ) {
			$downloadable_items[] = $item;
		}
	}

	foreach( $downloadable_items as $item ) {
		print_r( $item->get_meta('_wcj_product_input_fields_local_1') );
	}

	foreach( $downloads as $index => &$download ) {
		$recipient_name = $downloadable_items[ $index ]->get_meta( '_wcj_product_input_fields_local_1' );
		if ( $recipient_name ) {
			$download['download_url'] .= '&recipient=' . urlencode( base64_encode( $recipient_name ) );
		}
		
	}

	return $downloads;
}
add_filter( 'woocommerce_order_get_downloadable_items', 'pbi_downloads', 99, 2 );